JPS63164560A - Private branch exchange - Google Patents

Abstract

PURPOSE:To control also a telephone terminal equipment for power failure only by two calling lines similarly to a general telephone terminal equipment by sending a power failure restoring signal from a private branch exchange to the telephone terminal equipment for power failure through the calling lines. CONSTITUTION:At the time of power failure, a switching circuit 1 is restored, a subscriber's line is directly connected to a trunk line and a private branch exchange is by-passed. At that time, a power failure telephone circuit 51 in the power failure telephone terminal equipment 5 is connected to the subscriber's line and telephone service based upon a station exchange is secured through the trunk line. When power failure is restored, the switching circuit 1 is returned to its operating state, the trunk line is connected again with an office trunk 4 and the subscriber's line is connected again with a response detecting circuit 6. Simultaneously, a power failure restoring signal is sent from a power failure restoring device 7 to the power failure telephone terminal equipment 5. Consequently, the equipment 5 switches connection with the subscriber's line from the circuit 51 to an exclusive telephone set circuit 52 to restore the normal state.

Description

[Detailed Description of the Invention] [Summary] When a power outage is restored, a power outage recovery signal is sent from a private branch exchange to a power outage telephone terminal device, and the power outage telephone circuit of the telephone terminal device is switched to a dedicated telephone circuit, thereby producing a power outage telephone terminal device. Similarly to general telephone terminal equipment, it can be controlled using only two communication lines.

[Industrial application field]

The present invention relates to a private branch exchange, and more particularly to an improvement in a private branch exchange that allows a power outage telephone terminal device to switch from a power outage telephone circuit to a dedicated telephone circuit when a power outage is restored.

The connection between the private branch exchange and the power outage telephone terminal device, which has a dedicated telephone circuit for multi-function telephone services provided by the private branch exchange and a power outage telephone circuit for which only the telephone service provided by the central office exchange, is normally connected to the telephone line and the power supply line. A general telephone terminal device having only a dedicated telephone circuit is connected by 2fl.

Since the installation position of the telephone terminal device for power outage is not fixed, it is necessary to provide a four-wire telephone terminal device interface in all the exchanges, which is uneconomical.

Furthermore, the connection work between the private branch exchange and the power outage telephone terminal equipment is more labor-intensive and uneconomical than that for ordinary telephone terminal equipment.

Therefore, it is desired to provide a private branch exchange that can connect a power outage telephone terminal device with two wires in the same way as a general telephone terminal device.

[Conventional technology]

FIG. 3 is a block diagram of a conventional private branch exchange.

In the figure, 1 is a switching circuit, and normally the power supply (-24
V), the relay E is operating, and the relay T of the power outage telephone terminal device 5, which is supplied with power from the power line, is also operating.

Therefore, a dedicated telephone circuit 52 is connected to the line circuit 2 through which the multifunction telephone service of the power outage telephone terminal device 5 can be received through contacts e O and e I of the activated relay E. Further, the office line trunk 4, which is connected to the line circuit 2 by the network 3, is connected to the office line through activated contacts e2 and e3.

In the event of a power outage, relay E will be restored and its contact e
At 01 e'+e''He', the subscriber line is directly connected to the central office line and the private branch exchange is bypassed.

In addition, the relay T of the power outage telephone terminal bag M5 is also restored as power is no longer supplied by the power line, and the power outage telephone circuit 51 is connected to the subscriber line through the restored contacts to and t+, and is connected to the central office exchange via the central office line. Telephone service is ensured.

When the power outage is restored, the relay E of the switching circuit 1 and the relay T of the power outage telephone terminal device 5 operate again, returning to the normal state.

[Problem that the invention seeks to solve]

In a conventional private branch exchange, it is connected to a general telephone terminal device by two wires, a telephone line, but a telephone terminal device for power outages is
It is connected by four wires: a telephone line and a power line.

Therefore, the private branch exchange has a two-wire telephone terminal device and a four-wire power outage telephone terminal device mixed together.

Moreover, since the purpose is not to specify the housing location of the telephone terminal equipment for power outages, the private branch exchange side
There is an uneconomical problem in that all 4-wire telephone terminal interfaces must be provided. Furthermore, the construction of four lines has the problem of being time-consuming and uneconomical.

[Means for solving problems]

FIG. 1 is a block diagram of the principle of the present invention.

In the figure, 2 is a line circuit that connects to a subscriber line having a telephone terminal bag W5 for power outages, 3 is a network that connects the line circuit 2 to the office line trunk 4, and 1 is a network that connects the subscriber line to the line circuit 2 in normal cases. The outgoing line of the office line trunk 4 is connected to the office line, but in the event of a power outage, a switching circuit is used to disconnect the line circuit 2 and the office line trunk 4 and connect the subscriber line directly to the office line. be.

Reference numeral 7 relates to the present invention, and is provided in common to the private branch exchange, and generates a power failure recovery signal when the power is restored and the power is turned on to the private branch exchange. 6 relates to the present invention, and is dedicated to the power outage telephone circuit 51. A response detection circuit that sends a power outage recovery signal to the power outage telephone terminal device 5 having a telephone circuit 52, detects a response indicating switching to the dedicated telephone circuit 52, and connects the subscriber line to the line circuit 2. be.

[Effect]

In the event of a power outage, the switching circuit 1 is restored, the subscriber line and the office line are directly connected, and the private branch exchange is bypassed.

In the power outage telephone terminal device 5, the power outage telephone circuit 51 is connected to the subscriber line at this time, and the telephone service by the central office exchange is secured via the central office line.

When the power outage is restored, the switching circuit 1 returns to the operating state, the office line is again connected to the office line trunk 4, and the subscriber line is again connected to the response detection circuit 6. At the same time, a power failure recovery signal is generated by the power failure recovery signal device 7 and sent to the power failure telephone terminal device 5 via the response detection circuit 6.

The power outage telephone terminal device 5 receives the power outage recovery signal, switches the connection to the subscriber line from the outage telephone circuit 51 to the dedicated telephone circuit 52, and responds that the switching is complete. When the response detection circuit 6 detects the response, it connects the subscriber line to the line circuit 2 and restores the normal connection state.

In this way, the telephone circuit of the power outage telephone terminal device 5 can be switched from the private branch exchange using only the two subscriber lines used for telephone calls, so all the telephone terminal device interfaces on the private branch exchange side are the same. This makes it possible to realize an economical private branch exchange, which requires the same line construction work for power outage telephone terminals as for general telephone terminals.

〔Example〕

The present invention will be specifically explained below with reference to illustrated examples.

FIG. 2 is a block diagram of a private branch exchange according to an embodiment of the present invention. The same reference numerals indicate the same objects throughout the figures.

In Fig. 2, 1 connects the subscriber line to the private branch exchange through contacts e O and e I by the operation of relay E during normal operation.
This is a switching circuit that connects the outgoing line of the office line trunk 4 to the office line at contacts e it and e 3.

When a power outage occurs, since a small-scale private branch exchange like the one in this example does not have a storage battery, relay E is restored and the office line is directly connected to the subscriber line, bypassing the private branch exchange.

On the other hand, in the power outage telephone terminal device 5, the relay T that was operating because the power supply from the subscriber line is lost due to the power outage.
2 is restored, the power outage telephone circuit 51 is connected to the subscriber line by the restored contacts t2°, t2' and the contacts t1°, ti' of the relay T1 which is not operating, and the telephone call is made by the central office exchange via the central office line. Service is ensured.

When the power outage is restored, relay E of switching circuit 1 operates, the office line and office line trunk 4 are reconnected, and the subscriber line is also connected to the private branch exchange, but relay P of response detection circuit 6 is activated. Since it is not operating, the subscriber line is not yet connected to the line circuit 2, and the power outage telephone terminal device 5 is also connected to the power outage telephone circuit 51.

Further, upon power recovery, the signal oscillator 71 of the power failure recovery signal device 7 oscillates a 768 KHz power failure recovery signal, and sends the power failure recovery signal to the response detection circuit 6 via the transformer TS. The power failure recovery signal passes through the capacitor, CB, and contacts po, p+, and e0. e' to the subscriber line, and via the contacts t2°, t2' and the contact t1°tl+ of the power outage telephone terminal 5 to the capacitor CI.

C2 and is supplied to the rectifier 53.

The rectifier 53 rectifies the power failure recovery signal and connects the photocoupler PT.
makes the light emitting diode emit light, turns on the transistor,
Operate relay TI.

The activated contacts t1° and t11 are the ground of the response detection circuit 6, the resistor R, the light emitting diode of the photocoupler PE, the winding of the transformer TA, the contact pl, the contact e', the B line, and the contact t21.
Contact tl' - Winding of transformer TE - Converter 54 -
Winding of transformer TE - Contact t1° - Contact t2° - A line -
Contact e0 - contact po -) Lance TA winding - power supply (
-24v) to supply direct current to the converter 54.

Converter 54 operates relay T2 with its output and contacts t.
2°, t2', the relay T2 is self-holding, and the transformer T
The dedicated telephone circuit 52 is connected to the subscriber line via E.

A response indicating that the power outage recovery signal has switched from the power outage telephone circuit 51 to the dedicated telephone circuit 52 is represented by the creation of a loop between the A and B wires by the above circuit, and the response detection circuit 6 The response is detected by the light emission of the light emitting diode of the photocoupler PR, the transistor is turned on, and the relay P is operated. Activated contact 1”+1)
' connects the subscriber line to line circuit 2.

At this point, everything is restored before the power outage and normal telephone service is provided by the private branch exchange.

〔Effect of the invention〕

As explained in detail above, according to the present invention, telephone terminal equipment for power outages can also be controlled using only two subscriber lines, so all telephone terminal equipment interfaces such as distribution boards on the private branch exchange side are unified to two wires. , private branch exchanges become more economical. Also, in terms of construction, there will be two lines of work, which will save time and make it more economical.

[Brief explanation of the drawing]

Figure 1 is a block diagram of the principle of the present invention. FIG. 2 is a block diagram of a private branch exchange according to an embodiment of the present invention; FIG. 3 is a block diagram of a conventional private branch exchange. In the figure, 1 is a switching circuit, 2 is a line circuit, 3 is the network, 4 is the central office trunk, 5 is a telephone terminal device for power outages; 51 is a power outage telephone circuit; 52 is a dedicated telephone circuit; 6B response detection circuit, 7 indicates a power failure recovery signal device.

Claims (1)

[Claims] A line circuit (2) connected to a subscriber line, a network (3) connecting the line circuit (2) to a central office trunk (4), and a telephone terminal device for power outages in normal times. (5) connects the subscriber line connected to the line circuit (2);
In addition, the office line trunk (4) is connected to the office line, and in the event of a power outage, the line circuit (2) and the office line trunk (4) are connected to the office line.
) and a switching circuit (1) for directly connecting the subscriber line to the central office line. and the switching circuit (1), and a response detection circuit (6) is provided between the power failure recovery signal device (7) and the power failure telephone circuit (51). The response detection circuit (6) sends a response to the power outage telephone terminal device (5) having a telephone circuit (52), and the power outage telephone terminal device (5) is connected to the power outage telephone terminal device (5) from the power outage telephone circuit (51) to a dedicated telephone circuit. (52), and the response detection circuit (6) detects a response indicating completion of switching, thereby connecting the power outage telephone terminal (5) to the line circuit (2). private branch exchange.